消息：SQLSTATE [42S22]：未找到列：1054未知列＆＃39;字段列表＆＃39;，查询为

Question

我在下面的函数中不断收到此错误，不知道我做错了什么，试图将单个逗号更改为double但仍然存在错误。请协助。

public function atAssessed($year, $month, $region)
 {
  $select = $this->select()
        ->from($this, array('COUNT(*) as assessed, MONTH(assd_date) as month'))
        ->where('assd = ?', 1)
        ->where('assd_date >= ?', ($year - 1) . '-' . ($month + 1) . '-01')
        ->group('MONTH(assd_date)')
        ->order('assd_date');
        ($region != 0 ? $select->where('region = ?', $region) : '');
  return $this->fetchAll($select);
 }

下方的完整错误消息

  

消息：SQLSTATE [42S22]：找不到列：1054未知列   在'字段列表'中'enterprise.COUNT（*）已评估，MONTH（assd_date）'，   查询是：SELECT enterprise。COUNT(*) as assessed, MONTH(assd_date) AS month FROM enterprise WHERE（assd = 1）AND   （assd_date＆gt; ='2013-13-01'）GROUP BY MONTH（assd_date）ORDER BY   assd_date ASC